don't build libbt-vendor when vendor/ is missing am: d87c2ee912
am: 0bd8094c23

Change-Id: Ib64d82b25e9c2963cdf178787b53bf217aa63fd1
tree: f696a0dc2115747413b9be648bd67d9123b1d2d1
  1. libbt-vendor/
  2. Android.mk
  3. CleanSpec.mk